Category: distributions

At up to 3 m (9.8 ft) and 932 kg (2,055 lb), the leatherback is the worlds 4th largest reptile (after three crocodile species) and by far the largest turtle.

Along with two other marine species (above), the green (Chelonia mydas – inaturalist phot), and the hawksbill (Eretmochelys imbricata – Brittanica phot.), it breeds annually on certain São Tomé and Príncipe beaches.

Mouth and pharynx of Leatherback. Pinterest phot.

Leatherbacks feed almost exclusively on coelenterates (jellies or jellyfish) and swallowing them is added by long inward-pointing fleshy projections in the throat and pharynx (above). All of the worlds marine turtles are endangered species and the Gulf of Guinea Ids are important sites, guarded and studied by a number of NGO’s including the Príncipe Trust and ATM: the Association for the Protection, Research and Conservation of Sea Turtles in Lusophone countries.

The birds (avifauna) of the two islands are quite remarkable. Combined, São Tomé and Príncipe are only about 1000 km² and yet they are home to 28 unique endemic bird species of many different families. This is the highest density of bird endemism by area in the world. We have also discussed gigantism and dwarfism (above), poorly understood phenomena occurring frequently in island plants and animals.

São Tomé Grosbeak, Neospiza concolor, M. Melo phot and at right.

There have been several recent studies on the islands’ endemic bird species. Dr. Martim Melo of CIBIO, foremost latter-day student of this avifauna has shown that the genetic relationships of the seemingly extremely scarce São Tomé Grosbeak (above) reveal that it is actually a canary, not a grosbeak. It is thus now the world’s largest canary and a true island giant. It is 50% heavier than the next largest related species. As an island giant, it joins other São Tomé giant endemics like the Giant Sunbird, Dreptes thomensis, and the Giant Weave,r Ploceus grandis, the two largest species of their families in the world. These have been featured in earlier blogs. Two additional, less famous São Tomé species are the largest species of their respective families in Africa (above).

São Tomé Speirops, Xosterops lugubris. Phot. Lars Petersson]

SãoTomé Thrush, Turdus olivaceofuscus, Phot. Lars Petersson]

Under different systems, all of the endemic bird species could be considered rare and endangered since each unique species can only have a range of significantly less than 1000 km², which is the area of the two islands combined. In a sense, these unique species could be considered among the rarest in the world. One of the fathers of the “modern synthesis” (evolution + genetics), Prof. Ernst Mayr, wrote a paper in the magazine Science examining the levels of bird endemicity in relationship to island size and distance to mainland source. The extraordinary density of the endemic birds of our islands when compared with predicted levels (below) yield a separate third curve; a phenomenon he simply illustrated but with no attempt to explain it.

The status of nine of the São Tomé endemics is “threatened” according to modern ornithologists; until recently, three of these have been considered “critically endangered”: the São Tomé Grosbeak (above), the Dwarf Olive Ibis and the São Tomé Fiscal Shrike (below)

São Tomé Fiscal Shrike, Lanius newtoni. Phot. L. Petersson

Dwarf Olive Ibis, Bostrychia bocagei. Phot. L. Petersson

A recent paper by Dr. Ricardo de Lima (below) and colleagues is an examination of the ranges and population status of these three endemic birds. They found that the south-west central region of the island, most of which is included in the São Tomé Obô Natural Park, has the highest potential for the Critically Endangered birds, and that indeed all three species were associated with native forest. The ibis prefers high tree density, while the fiscal selects low tree density and intermediate altitudes. “Despite very restricted ranges, population sizes seem to be larger than previously assumed. These results suggest that the fiscal and grosbeak might be better classified as ‘Endangered’, while the ibis should maintain its status under different criteria, due to a very restricted range during the breeding season.”

The colorful and varied endemic bird fauna of São Tomé and Príncipe is a flamboyant if somewhat enigmatic example of speciation and evolution over time. As the graph above illustrates, there are more endemic species by unit area than one would predict, even in light of the near proximity of the African mainland. Although the unique species are now reasonable well-described compared with other elements of the fauna, there is still a great deal to be learned.

The only venomous snake on the islands is the Forest Cobra “Cobra preta”, of São Tomé, fairly common in most inland habitats, and the source of some controversy over the years (see blog, May 2009). Whether it is naturally occurring i.e., the descendent of a disperser like many of the terrestrial uniques, or whether it was brought by man in some manner has been a point of discussion for some years. For a long time the few scientists working on the islands have referred to this species as Naja melanoleuca, a large cobra which is widespread on the African mainland (below).

From blog, May 2008: Within the House of Slytherin II. (left) Naja melanoleuca. Cowyeow photo]

A recent publication by Dr. Luis Ceríaco et al. (National Museum of Natural History and Science) suggests that the São Tomé cobra is a naturally occurring endemic; they have named it Naja peroescobari, after one of the Portuguese navigators who discovered the island in 1471. The authors distinguish Cobra preta from the mainland species by slightly larger size, a different color pattern underneath, and the arrangement of some scales in the throat area.

While on the subject of reptiles, recent expeditions have afforded us with more knowledge, along with some outstanding new photos of related island endemics:

São Tomé “jita”. Boaedon (Lamprophis sp). Phot Lars Petersson

Príncipe “jita”. Boaedon (Lamprophis sp). Phot. Andrew Stanbridge

We know these two island species are distinct from one another and from close mainland relatives on the basis of pattern and molecular evidence. The big island species (above) has a pattern of lines along the back; that of Príncipe is a series of blotches. A group of us led by Dr. Luis Ceríaco is in the process of assigning new names to these island two populations.

Hugulay Maia (insert, below) is a young São Toméan from the big island who has been interested in the natural history of the Gulf of Guinea Islands for most of his life. He and his mentor, the late Angus Gascoigne, have appeared in this blog a number of times over the years, and Hugulay is currently a PhD candidate in marine ecology at the University of Santa Catarina in Brazil. He has just produced a durable guide to the marine species most frequently encountered by local fishermen, pictured below. As a scientist he will be a strong, valuable asset to the islands’ fauna and flora and to the government, especially with respect to the conservation of its natural marine resources.

Quade of STeP UP has been a bulwark of our field work and education program since the beginning in 2001. He is a translator, teacher of English and many other useful things. Chase is a consultant from Washington D.C., examining possibilities for expansion and modification of our Gulf of Guinea Project in the future.

The Parting Shot:

Me at Jockey’s Bonnet, Principe Id. This is an ancient island off the east coast that harbors a currently recognized endemic subspecies of finch.

PARTNERS
Our research and educational expeditions are supported by tax-deductable donations to the “California Academy of Sciences Gulf of Guinea Fund*.” We are grateful for ongoing governmental support from the Republic of São Tomé and Príncipe, and especially to Arlindo de Ceita Carvalho, Director General, Victor Bonfim, and Salvador Sousa Pontes of the Ministry of Environment and to Faustino de Oliviera of the Department of Forestry for their continuing authorization to collect and export specimens for study, and to Ned Seligman, Roberta dos Santos, Anita Rodriguez and Quintino Quade of STePUP of Sao Tome, our “home away from home”. GG IX, X and XI were funded in part by a generous grant from The William K. Bowes Jr. Foundation, and substantial donations from Rod C. M. Hall, Mr. and Mrs. Henri Lese, Mr. and Mrs. John L. Sullivan Jr., Mr. and Mrs. John Sears, in memory of Paul Davies Jr. and a heartening number of Bohemian friends. We are grateful for the support of Roça Belo Monte (Africa’s Eden-Príncipe) for both logistics and lodging.
*55 Music Concourse Drive, Golden Gate Park, San Francisco CA 94118 USA

The scientific name of each living species is like the handle on a drawer, enabling biologists to pull it open and learn all that has been observed and written about that species. These names, usually Latinized or in Greek, are the most basic building blocks in any attempt to describe the Earth’s natural habitats and ecological systems… literally the first step in the exploration of unknown or poorly known habitats. First question asked: what’s living there? If no one has noted a species before, we communicate its existence by describing it and giving it a name..

Our first expedition to the islands of São Tomé and Principe was in 2001, and the first new island species our scientists described was a beetle (below). Although it was collected high in the mountains on São Tomé during our first expedition, the new name was actually published four years later.

Straneo seligmani Kavanaugh, a new carabid beetle from near Macambrara, São Tomé at about 1100 m. Straneo is an endemic genus; its two known species occur only on this island..

It takes a lot of time to recognize and describe a new species; after all, the scientist has to know all of related species that the new species is not! This new beetle was named for Ned Seligman, Director of STeP UP, an island NGO. We have worked closely with STeP UP since the beginning in 2001.

Another special insect collected on our first expedition was an ant species new to science; it was described a few years later (below).

Tetramorium renae Garcia, Fischer & Peters from Bom Sucesso, São Tomé

During the past 17 years, our teams have undoubtedly collected many new insect species on São Tomé and Príncipe. But it takes a lot of time for entomologists to sort through our nearly two decades of island specimens.

The bryophyte flora (mosses, liverworts and hornworts) was poorly known before tireless Jim Shevock joined us on several recent expeditions. The new moss species described by Jim and his colleagues (below) is but the first of many awaiting publication.

Porotrichium saotomense Enroth & Shevock from São Tomé

In fact, Jim and his colleagues such as Dr. Cesar Garcia the University of Lisbon (above) have added 46 mosses, 66 liverworts and 3 hornworts to the flora of the islands so far, suggesting that this group is surprisingly rich these ancient islands .

Botanists at work on Príncipe, GG XI. A. Stanbridge phot.]

Lizards are usually a fairly conspicuous part of any environment during both day and night (geckos), so it might be expected that the lizard fauna of the two islands would be well known. Not so; our teams have described one new species and are working on a second.

Principe, 2008

Hemidactylus principensis Miller, Sellas & Drewes. Weckerphoto.

This nocturnal gecko of Príncipe Island shares a unique character with its nearest relative, H. greeffii of São Tomé – the absence of the last digit on the thumb (below).

An additional new species was described a couple of years ago by Dr. Luis Ceriaco of the University of Lisbon. The skink lives on Tinhosa Grande, an islet off the south coast of Principe.

Trachylepis adamastor Ceriaco, Tinhosa Grande island.

Several earlier blogs have featured our mushroom work ; in earlier times, there were only about twelve known species on the islands. Drs Dennis Desjardin and Brian Perry collected more than 200 kinds during GG II and III expeditions, and their analysis of these specimens is ongoing.

The description of Phallus drewesi Desjardin & Perry (above) was the first of the new mushroom descriptions and for obvious reasons, its shape and size received some notoriety- it is the second smallest mushroom in the genus Phallus, and it grows limp. The publication was featured on a humorous American radio show called “Wait, Wait. Don’t Tell Me!”

Scytinopogon havencampii Desjardin & Perry of Principe (above) was named in honor of a group of friends who helped fund this particular work. Earlier this year, four additional new species from both islands were described by Desjardin & Perry and just this week, the same authors published yet another scientific paper in the international journal, Mycosphere. They recognized 31 hitherto unreported fungus species on the islands, and these include ten new ones; three of the new species names commemorate individuals who have helped support our expeditions: Campanella burkeii, Gymnopus rodhallii and G. billbowesii.

Campanella burkei Desjardin & Perry from Principe Island.

Gymnopus rodhallii Desjardin & Perry from São Tomé.

Several of our expeditions have included workers studying inshore marine organisms. Then graduate student Dana Carrison-Stone published the descriptions of two new species of barnacles she discovered during dives in 2008 (GG III).

Conopea saotomensis Carrison-Stone, Van Syoc, Williams & Simison. The other new species, C. fidelis, was described in the same publication. Both were collected off Príncipe Island and formed part of the research for her MSc degree]

Carrison-Stone in the field off Príncipe, GG III

Drs Tomio Iwamoto and Luis Rocha have both worked on our Gulf of Guinea expeditions, Tomio since the very beginning in 2001. Luis has led several separate diving expeditions there including GG X in 2016 .

Serranus pulcher Wirtz & Iwamoto (above) was described from a specimen Tomio caught by rod and reel off the pier of Ned Seligman’s house on the northeastern shore of São Tomé during GG II. Luis named Sparisoma choati Rocha, Brito & Robertson (below), a new parrotfish from the waters of Príncipe just last year (Rocha phot).

Amphibians are not supposed to occur on islands that have never been attached to a mainland source. This point has been made about oceanic islands ever since islands have been studied (see early blogs in this series); for obvious reasons (salt water) the same is true for freshwater fishes. Nevertheless, São Tomé may well be unique in having eight species of endemic amphibians, two of which were discovered and described by members of our Gulf of Guinea expeditions.

Phrynobatrachus leveleve Uyeda, Drewes & Zimkus of São Tomé (above) was discovered to be genetically distinct from its Príncipe relative, P. dispar as early as 2007 by Dr. Josef Uyeda, a two-time expedition member.

A similar situation exists with the very similar small green tree frogs of the islands. Dr. Rayna Bell discovered that the two island populations were actually quite distinct from one another and named the Príncipe species, Hyperolius drewesi Bell, a great honor.

Hyperolius drewesii Bell of Príncipe. Gasparini phot.

Finally another graduate student contributor to our island work on São Tomé and Príncipe is Matthias Neumann of the University of Kassel, Germany. His fieldwork on flatworms (aka geoplanids) of the islands led to the description of five new species in a recent publication. His work is particularly relevant as many of these strange, brightly colored species are known predators of land snails, and the snail species of São Tomé and Príncipe are more than 70%endemic, found nowhere else in the world.

Various geoplanid flatworms from São Tomé among which are five new species described by Sluys and Neumann.

We will be returning to the islands once again in November.

Here’s the Parting Shot:

Rio Porco, at the remote southern end of Príncipe not far from new Scops owl species site (see last blog). A. Stanbridge phot.

PARTNERS

Our research and educational expeditions are supported by tax-deductable donations to the “California Academy of Sciences Gulf of Guinea Fund*.” We are grateful for ongoing governmental support from the Republic of São Tomé and Príncipe, and especially to Arlindo de Ceita Carvalho, Director General, Victor Bonfim, and Salvador Sousa Pontes of the Ministry of Environment and to Faustino de Oliviera of the Department of Forestry for their continuing authorization to collect and export specimens for study, and to Ned Seligman, Roberta dos Santos, Anita Rodriguez and Quintino Quade of STePUP of Sao Tome, our “home away from home”. GG IX, X and XI were funded in part by a generous grant from The William K. Bowes Jr. Foundation, and substantial donations from Rod C. M. Hall, Mr. and Mrs. Henri Lese, Mr. and Mrs. John L. Sullivan Jr., Mr. and Mrs. John Sears, in memory of Paul Davies Jr. and a heartening number of Bohemian friends. We are grateful for the support of Roça Belo Monte (Africa’s Eden-Príncipe) for both logistics and lodging.

Note: This blog and the preceding one are dedicated to the memory of our friend Bill Bowes, of the William K. Bowes Jr. Foundation, who graciously lent his personal encouragement to and support for the GG IX, X and XI expeditions. We of the Gulf of Guinea team and the California Academy of Sciences will miss him very, very much.

The São Tomé weaver (Ploceus sanctithomae] is a forest species known only from the big island. Phot. P. Loureiro.
During Gulf of Guinea IX, two years ago, our education effort was focused on the endemic bird species of both islands; as mentioned before, the bird fauna is hugely important; the two islands have perhaps the highest number of unique bird species by area in the world, 28 endemics/1000km ².

The São Tomé Prinia. (Prinia molleri). The “Truqui” is found only on the big island and is probably the most common endemic species there (top photo. P. Loureiro.) As we visited the classrooms, each student got a pair of plastic binoculars (they work!), and our booklet that highlights some of the most beautiful species on both islands and their natural history (above, left and right. phots by A. Stanbridge).

And, expedition patches are given by the teachers to 10 students who do the best work each year. (photo by A. Stanbridge, above)

Our intent is always to instill in the kids a sense of ownership for these species for their uniqueness and beauty: “No one else has these, even on the other island!” The image below was taken by our senior educator, Roberta Ayres, but it might have been made anywhere little kids play. Regardless, we never preach in our classroom presentations; we present the species of the flora and fauna as rare and beautiful.

Our Gulf of Guinea Islands project is indeed multiplex, and some of the most interesting scientific discoveries in past years have been made by graduate students in pursuit of higher degrees.

Recently, Ana P. Coelho (above middle), received her MSc degree in conservation biology from the University of Lisbon; her thesis advisor was our long-time colleague, Dr. Ricardo Lima (left), whose earlier PhD thesis was also based on the island ecology.

Field assistant Octavio, mist-nettng (A. Coelho phot.)
Ana studied the roles of birds in dispersing seeds on São Tomé. Some 18 species of birds, all endemic, were systematically mist-netted (above), and ring-banded (below). Their droppings were studied over time to determine what seeds the fruit-eating (frugivorous) species were eating. The field/data collection part of the study was several months in duration.

Of the 18 species captured and released, nine were frugivorous, and Ana showed that the great majority of seeds they ate were in the fruit of endemic or native plant species. Some species of non-native plants were ingested and dispersed as well.

This relationship among endemics makes evolutionary sense. We know that the accumulation of genetic (and morphological) change leading to the evolution of new species takes isolation and time. This is as true for the consumer (the birds) as it is for the energy source (the fruit of the plants). So one can suggest that the birds and the seed plants upon which they feed co-evolved over thousands of years. The birds benefit from the fruits of the plants and in turn, the plants’ seeds are carried to distant environments (along with fertilizer) in the bird droppings.

The São Tomé speirops (above) is by far the most frequent seed disperser; Ana found this endemic produced 84% of all droppings containing seeds. .

However, it should be noted that in this case, the birds are also responsible for a rather difficult conservation issue. Through seed dispersal of endemic plants, they are contributing to native forest regeneration, but because they also disperse a number of non-native plant species, the birds are also involved in biological invasion – the spread of alien species..

Above is an additional endemic predator/prey relationship: a São Tomé house snake ingesting a São Tomé giant tree frog; both species are endemic to the big island. (Matthias Neumann phot. )

Another recent graduate student contributor to our scientific knowledge of Gulf of Guinea biology is Matthias Neumann (below), who recently completed his MSc in biology at the University of Kassel in Germany.

(M. Neumann phot)

Matthias spent a couple of months in the islands last year collecting and studying geoclads (flatworms), many species of which are known to be predatory on snails.
We have made the point in earlier blogs that these flatworms are potentially very important because the land snail fauna of both islands is over 70% unique, and if these flatworms are recent arrivals, they may pose a real danger to the existence of the endemic snails. Prior to Matthias’ field investigations almost nothing was known about the island flatworm fauna except for some random observations by some of us working in the forests (see earlier blogs).

Mathias (left) with field assistant, Lionel; a geoclad feeding on a terrestrial snail (right). M. Neumann phots.
Matthias was successful in completing his degree, and his work has recently been published: Sluys R., M. Neumann, R.F. de Lima, & R, C. Drewes. 2017. Land flatworms (Platyhelminthes, Geoplanidae) of São Tomé: a first account on their diversity, with the description of five new species. Zootaxa 4221 (3): 291–322.

Matthias estimates that there at least as many additional undescribed flatworm species on the islands awaiting identification and study. Two of the species he has discovered so far are definitely snail predators. If these two species are long-time inhabitants of the islands, it is likely they have co-evolved with their snail prey, a situation probably not unlike the endemic bird/endemic plant relationship studied by Ana Coelho. There is so much more to be learned in these islands.

As Ana’s and Matthias’s photos above suggest, both of these young scholars are born naturalists, interested in a wide range of living species. The images include a freshwater blenny, a freshwater shrimp, a São Tomé house snake and a giant sunbird, all endemic or native to the islands.

The Parting Shot:

Dr. Cesar Garcia, of Lisbon, working on Principe. Fieldwork is always exhausting, occasionally painful but forever a joy!
PARTNERS
Our research and educational expeditions are supported by tax-deductable donations to the “California Academy of Sciences Gulf of Guinea Fund*.” We are grateful for ongoing governmental support from the Republic of São Tomé and Príncipe, and especially to Arlindo de Ceita Carvalho, Director General, Victor Bonfim, and Salvador Sousa Pontes of the Ministry of Environment and to Faustino de Oliviera of the Department of Forestry for their continuing authorization to collect and export specimens for study, and to Ned Seligman, Roberta dos Santos and Quintino Quade of STePUP of Sao Tome, our “home away from home”. GG IX, X and XI have been funded in part by a generous grant from The William K. Bowes Jr. Foundation, and substantial donations from Rod C. M. Hall, Mr. and Mrs. Henri Lese, Mr. and Mrs. John L. Sullivan Jr., Mr. and Mrs. John Sears, in memory of Paul Davies Jr. and a heartening number of Bohemian friends. We are grateful for the support of the Omali Lodge (HBD-São Tomé) and Roça Belo Monte (Africa’s Eden-Príncipe) for both logistics and lodging.
*California Academy of Sciences
55 Music Concourse Dr.
San Francisco, CA 94118

Principe Island looking south toward Rio Porco, site of the new discovery. A. Stanbridge phot.

The birds of São Tomé and Príncipe are truly spectacular and by rights should be a major birdwatchers tourist destination. The island avifauna is probably the best understood of the terrestrial vertebrates and since our research concentrates on poorly known species, our expeditions have never included an ornithologist and the incredible bird life appears only occasionally in this blog. Recent events require further attention.

Birds have fascinated amateurs and scientists alike from very early on in the history of science; because of this strong and enduring attention, the discovery of new, undescribed bird species is rather infrequent and thus quite exciting.

The Principe scops owl, valley of the Rio Porco. phot P. Verbelen

After some 90 years of rumors and speculation, Felipe Spina of Fauna & Flora in Santo Antonio and Philippe Verbelen of Belgium discovered there is, in fact, an owl species living on Príncipe Island! It has finally been seen, photographed (above) and recorded by these gentlemen in the remote southern valley of the Rio Porco, in July, 2016.

Scientists know very little about the new owl beyond discovery that it exists. We do know that the call of the little owl is very different from the call of other known scops species.

The Sao Tome scops owl, Otus hartlaubi. Phot. Hotspot Birding.

But how many owls are there in these rugged, trail-less valleys, and how widely are they distributed on the island? Is it really a new species, genetically distinct from the nearby São Tomé scops owl, Otus hartlaubi? (above) There are three widely distributed species on the mainland, plus two found exclusively in different East African coastal forests (below), and there is another island endemic in the Indian Ocean (Socotra).

Sokoke scops owl, known only from the Arabuko-Sokoke Forest of coastal Kenya. phot. of red phase by Syczek Brunatny.]

How do the Gulf species relate to other scops owls? These basic questions can only be answered by detailed genetic and morphological examination of a live specimen; future work is being planned and led by Dr. Martim Melo of CIBIO, Porto, Portugal, the foremost expert on the birds of São Tomé and Príncipe. Martim first heard this owlet in 1998 and has been searching for it ever since!

The non-wading bird assemblage of São Tomé and Príncipe may represent the highest level of unique species in the world, by area. Above is an image comparing the bird faunas of the two Gulf islands with the famous Galapagos, a much larger archipelago in the Atlantic Ocean. The Galapagos are justly famous, but it is interesting to note that the majority of endemic bird species there evolved from a very few colonizers; for instance, the celebrated Darwin’s finches are all each others’ closest relatives.

The São Tomé and Príncipe avifauna is much richer in different evolutionary lineages; these range from endemic starlings (above), weavers and an oriole to unique sunbirds, kingfishers and flycatchers.

Sao Tome giant weaver. Phot by. Nik Borrow

Among this rich assemblage are several species that are excellent examples of the phenomena of island gigantism and dwarfism discussed in earlier blogs. For instance, the largest weaver bird in the world (70+ species) is the giant weaver (Ploceus grandis, above), endemic to São Tomé. The world’s largest sunbird (Dreptes thomensis, below) is a species also unique to São Tomé.

Sao Tome giant subird. phot. Fabio Olmos

Sunbirds are Old World, nectar-feeding equivalents of the New World hummingbirds. The two groups are not closely related, but they converge greatly in appearance and behavior because they fill the same ecological niche in their respective geographic areas.

Above, the giant sunbird is shown on the right, together with Newton’s sunbird, itself an endemic species; photo taken after banding by Dr. Martim Melo. Like the giant hummingbird of the Andes, the giant hummingbird is also drab in coloration.

São Tomé dwarf ibis. phot. Nik Borrow

There are 27 species of ibis, world-wide; the smallest by far is the São Tomé dwarf ibis, (above, Bostrychia bocagei); there is but a single population of these birds living in the remote southern forest of the big island, and they are severely threatened by poaching for food and the expansion of a large oil palm plantation to the south.

Many of the unique birds on the two islands are singletons; i.e. they are the only representative of their group on one of the two islands, with no relatives on the other.

São Tomé oriole, Oriolus crassirostris.

These endemic flycatchers are also sexually dimorphic]

Among the other endemic species are pairs represented by one closely related species on each island. When these species are each other’s closest relatives, they are called “sibling species; however, they can be very similar in appearance and behavior because they fill the same ecological niche on each island- not because they are each others’ closest relatives.

Each island has a thrush species; the Principe thrush (right), newly discovered, is obviously similar and related to that of the big island, but they are not necessarily each others’ closest relatives. Dr. Melo has determined by genetic study that their ancestral colonizers arrived at very different times from the mainland. Recall that Principe is geologically twice as old as Sao Tome. If the ancestor of the thrush on Sao Tome dispersed from Principe, they would be siblings, but as Dr. Melo has shown, both species descended from mainland ancestors at different times.

Many other intriguing bird pairs are found on the islands.

A number of much earlier workers considered some of the islands’ bird species so distinct that they deserved their own generic names, and traditionally, there were seven unique genera recognized on the islands (including the giant sunbird, and Speirops, above). Dr. Melo has shown that even though some of these are dramatically different in appearance from relatives, this similarity is the result of relatively recent selection pressures and genetically, they should still be included within pre-existing genera.

Note: This blog, Part II to follow, is dedicated to the memory of our friend Bill Bowes, of the William K. Bowes Jr. Foundation, who graciously lent his personal encouragement and financial support to and for the GG IX, X and XI expeditions. We of the Gulf of Guinea team and the California Academy of Sciences will miss him very, very much.

The new header image of Príncipe Island from the east (above) was made by our friend, Jan Fourie, of Africa’s Eden; Príncipe is 31 million years old and was much, much larger in the Oligocene.

Revisiting the famous “Bode of Bombaim” with cobra skin in hand, along with our indefatigable photographer, Andrew Stanbridge (left). This area of central São Tomé seems to harbor sizable numbers of forest cobras (Naja nigricollis), the islands’ only venomous snake species, thought to have been introduced by early Portuguese settlers. We have extracted DNA from Bode’s skins to test this hypothesis.

Some more updates from GG IX: Dr. Luis Mendes is completing his monograph on the butterflies of the islands. He informs us that he collected about 400 specimens during GG IX.

His collections represent 40 species of six families from both islands with new records and observations of endemics.

Jim Shevock (above) of CAS, is a veteran of three past Gulf of Guinea expeditions, and has just published a sixth scientific paper on bryophyte flora of the islands. It is plain that the bryophyte flora of the islands is much more diverse than had been thought and Jim has many more species to be and new ones to describe especially. Jim will be a participant on GG XI in November.

Dr. Rayna Bell (above left), now of the Smithsonian Institution, continues her work with the treefrog genus Hyperolius. The opportunity arose for us to sample the southern part of the Obo Natural Forest on São Tomé where, it turns out, the giant tree frog (H. thomensis) is much more easily found and observed. There are some intriguing biological issues involving genetic interaction between these two species which are so different in size and color (above right), and Rayna continues her studies of them and the giant tree frog (Leptopelis) of Príncipe.

Drs Bell and Ricardo Lima in the forest of São Tomé, inland of Angolares.

On the academic side of things, the Island Biology Conference held in July at the University of the Azores on Terciero Island was a great success with over 400 scientists and students in attendance for a week. At the first such meeting held in Hawaii there were only two presentations on Gulf of Guinea science; in the Azores, we had a day-long symposium featuring talks on many aspects of island biogeography and conservation.

Such meetings facilitate useful interactions between scientists and students, allowing them to avoid overlap of effort and at the same time promoting cooperation; we were very heartened by the increase in the number of people doing research and educational activities on the islands.

Drs Mariana Carvalho and Ricardo Lima discuss various São Tomé/Principe
projects (above). Both are authorities on forest ecology, the Gulf of Guinea bird fauna and the interactions of human populations with the environment. After several years of work in Mozambique, Mariana is returning to the islands where she will continue her work under the auspices of Birdlife International. Ricardo was one of the organizers of the symposium.

In several previous blogs I have mentioned Hugulay Maia, a Sao Tomean from the town of Angolares on the southeast coast. We first met Hugulay years ago through his mentor and friend, Angus Gascoigne, an accomplished resident naturalist on São Tomé. Tragically, Angus passed away a few years ago; he would have been very proud to learn that Hugulay is now pursuing PhD research on the coastal fishes of the islands.

Maia was a member of the GG X marine team, as was his doctoral advisor, Dr. Sergio Floeter of University of Santa Catarina, Brazil. A few months ago in Lisbon (below), he presented part of his thesis work to the Gulbenkian Foundation in Lisbon, one of the major funders of his work on coastal fishes.

Our next terrestrial expedition, GG XI will be in November and will be the topic of the next blog.

PARTING SHOT.

Here at Praia Jalé in southeastern São Tomé is a leatherback sea turtle (Dermochelys coriacea), one of several species of ocean-going sea turtles that breed on the islands annually. Looking on are our old friends Bastien Loloum, his wife Delicia and kids Flora and David. Bas said: “The nesting turtle got surprised by sunlight and was just finishing up [laying eggs] as we arrived by her side. The picture was taken by a German tourist who was also staying at the lodge that same night.” This is the world’s largest turtle and the 4th heaviest reptile (after 3 monitor lizards). These giants can reach 2.13m (just under 7 feet) with a mass of 650 kg (1433 lbs)!

PARTNERS.
The research expeditions are supported by tax-deductable donations to the “California Academy of Sciences Gulf of Guinea Fund”* On the islands, we are grateful for ongoing governmental support, especially to Arlindo de Ceita Carvalho, Director General, Victor Bonfim, and Salvador Sousa Pontes of the Ministry of Environment, Republic of São Tomé and Príncipe for their continuing authorization to collect and export specimens for study, and to Ned Seligman, Roberta dos Santos and Quintino Quade of STePUP of Sao Tome http://www.stepup.st/, our “home away from home”. GG VIII, IX , X and upcoming GG XI have been funded by a generous grant from The William K. Bowes Jr. Foundation, and substantial donations from Mrs. W.H.V.“D.A.” Brooke, Thomas B. Livermore, Rod C. M. Hall, Timothy M. Muller, Prof. and Mrs. Evan C. Evans, Mr. and Mrs. John L. Sullivan Jr., Clarence G. Donahue, Mr. and Mrs. John Sears, and a heartening number of “Coolies”, and members of the Docent Council of the California Academy of Sciences. Once again we are deeply grateful for the support of the Omali Lodge (São Tomé) and Roça Belo Monte (Príncipe) for both logistics and lodging and to the Príncipe Trust for partial sponsorship of our on-going primary school education program during GG VII and GG VIII.

The Biodiversity Education team has been hard at work on our product for GG VIII, of April, 2014. The 2000 students we have been visiting since the 3rd grade are now in the 5th grade and will be moving on next year, so this is our last visit with them. We have produced a slightly more technical biodiversity booklet (livreto) for each of them. This cohort represents slightly more than 35% of the island studentsin their age group.

Just recently a great new book was published called The Monkey’s Journey, by Alan de Queiroz. An entire chapter (6) is based on our hypothesis as to how amphibians and many of the other unexpected, endemic animals originally crossed over to the islands from the mainland.

One of us has made an exciting discovery recently (see below) which prompts me to reacquaint readers with the amazing amphibian fauna of Sâo Tomé and Príncipe. As readers already know, there should not be any amphibians on these islands at all; they are true oceanic islands which have never been attached to the African mainland, and amphibians have no tolerance for saltwater. There are no native amphibians on the Galapagos or the Hawaiian Islands for this reason. Yet, there are seven species on our islands, possibly eight – all unique and found nowhere else in the world! The most unlikely of these is the famous “Cobra bobo” of Sâo Tomé.

The cobra bobo (Schistometopum thomense) is a caecilian, part of a group of amphibians only distantly related to frogs and salamanders. They are found almost exclusively in the Old and New World Tropics. About 25% of the 200 species lay eggs, the rest, including our cobra bobo give birth to living young (see above).

Although they look very much like earthworms, caecilians have backbones, teeth and a vertebral columns. (above lef-UCL photot). Most are burrowers although some are aquatic, but all caecilians lack legs, tails and have reduced eyes, and they are the only amphibians that have sensory tentacles located on each side of the head, between the nostril and the eye (above right – different species-J. Measey phot.). These are protruded to sense prey items and the environment.

The cobra bobo is widespread under moist leaf litter, old banana stems, etc from sea level to as high as 1400m, at Lagoa Amelia. Although they are totally harmless, they are widely feared by the islanders, which is the reason we use a cobra bobo cartoon for our expedition logo (see earlier posts). We are attempting to demystify it. One of the most interesting things about this endemic species is the distribution of its closest relative.

Note that several thousand km separate the two known species; the red ? indicates a single old specimen in Brussels from the Ituri region of Zaire that might also be a member of the same genus.

A frog unique to Sâo Tomé is Newton’s rocket frog, Ptychadena newtoni. There are over 50 species recognized on the African mainland, but this endemic is by far the largest of the genus, with females attaining lengths of over 60mm. This qualifies Newton’s rocket frog as a true “island giant.”

Newton’s rocket frog. above phot RCD- GGI, below A. Stanbridge,-GGVI

Early records suggested it is a frog of streams and rivers in the northern lower elevations, but we have found its larvae as high as Java, at 600m, and in recent years, Hugualay Maya of ABS has discovered the species in river drainages farther south down the west coast. (pink markers).

Known localities for Newton’s rocket frog. RCD construct

Frog larvae (or tadpoles as they are often known in English) are used in identification of species by scientists, as well as the study of adults and are formally described.

An extremely interesting fact about Newton’s rocket frog is the location of its closest relatives. Like the cobra bobo, the species of Ptychadena genetically closest to our island frog are eastern species, not Central or West African.

This study included 108 rocket frog samples from all over sub-Saharan Africa, including the Nile drainage, Madagascar and the Seychelles.

Another endemic island giant is Príncipe’s giant treefrog, Leptopelis palmatus. In fact, the first specimen ever collected and described nearly 150 years ago was a female measuring 110mm from snout to between the legs. This is the largest ever recorded for the genus. The largest specimen we have collected was a 108mm female, during GG I near Sundi.

There are a number of strange things about this species; the females are usually always dark to dull green, while the males come in a great range of color patterns, some quite bright (polychromatic- see below). Moreover, the largest males are usually less than half the size of the females (above and below). While we were the first to record its call, this is the one species on both islands for which we have no data for eggs or larvae. Most large females have been found in the lowlands of Príncipe, while males seem to be common up to 700m on the Pico.

Distribution of the Príncipe giant tree frog and its closest mainland relative, L. macrotis. This may suggest that the ancestor of both rafted from the Niger River delta into the Gulf of Guinea.

Both islands have small species of puddle frog, Phrynobatrachus, that are widely distributed on both islands in leaf litter, and breed in temporary puddles of water. Both island forms were thought to be the same species (they are tiny and remarkably similar to the untrained eye) until we discovered that they were genetically quite distinct species with physical differences.

The Príncipe puddle frog, Phrynobatrachus dispar, can be found in wet areas from sea level to the top of Pico do Príncipe. While we have its larvae and eggs, we have not yet described them. D. Lin phots-GG II.

The Sao Tome puddle frog, Phrynobatrachus leveleve is very similar in appearance to the Príncipe species but there are great genetic differences and physical differences as well. Like its relative on Príncipe, it is broadly distributed in wet areas from sea level to very high elevations. RCD phots, GG VI.

Its larval characteristics can be seen below.

Drawings: Dylan Kargas

Like the other amphibians, the distribution of the nearest relatives of our two island puddle frogs is intriguing.

According to a recent study, Príncipe’s puddle frog, P. dispar is most closely related to a population in the Caprivi Strip of Namibia, and together their nearest relative is P. leveleve of Sâo Tomé. The interesting thing to notice is that all of the other members of this lineage, called a clade and defined by the purple box, are East African species. This is reminiscent of the rocket frog and cobra bobo distributions.

Returning to island giants, we have the Sâo Tomé giant treefrog, Hyperolius thomensis. There are well over 200 species of this genus known from the African mainland, and females of this Sâo Tomé endemic are by far the largest at just under 50mm.

D. Lin phot- GG I

D.Lin phot. GG – I

Breeding pair of Sao Tome giant treefrog. D. Lin phot, GG II

This large flamboyant tree frog appears to largely be a tree canopy dweller. We have discovered that eggs are laid in water-filled holes in trees (phytotelmata). They can be heard calling from treetops but are extremely difficult to locate; in fact all of our specimens have come from a single locality at around 1100m; we monitor this locality every year and keep its exact location a secret. We have described the larval characteristics, below.

Drawings by Dylan Kargas

Our last endemic species is closely related to the Sâo Tomé giant tree frog, although it is much smaller and not so brightly colored: Hyperolius molleri, the oceanic tree frog. Since our work began, it is the only remaining amphibian that has been thought to inhabit both Sâo Tomé and Príncipe. In fact, years ago an early intern of mine, Katie Marshall, compared the two populations using mitochondrial genes and found no significant differences between them; they are certainly extremely similar morphologically ( see below).

Above, Weckerphoto GG III; below, RCD phot GG I

Recent work by Rayna Bell, our Cornell colleague (GG VI, VII) included a reanalysis of the two populations with more advanced technology, and indications are that the two populations may be quite distinct genetically. If this turns out to be the case, the Príncipe population will require much closer morphological examination and redescription, bringing the total number of endemic amphibians on our islands to eight!

While this small green tree frog appears to be a lower elevation dweller on Príncipe, on Sâo Tomé it reaches at least 1400m and can be heard calling at Lagoa Amelia. Like most other members of the genus, eggs are laid on leaves above water, the developing tadpoles ultimately wiggling out of the jelly mass and falling into the water for further development. We have studied the larvae of the big island form (the original Hyperolius molleri- the species was described based on a specimen from that island) and the characteristics are below.

Drawings by Dylan Kargas

The team leaves for the islands in early April; our mission for GG VIII will largely be on biodiversity education as I mentioned in the beginning, but we will continue to post on our progress while there.

PARTNERS
We are most grateful to Arlindo de Ceita Carvalho, Director General, Victor Bomfim, and Salvador Sousa Pontes of the Ministry of Environment, Republic of São Tomé and Príncipe for their continuing authorization to collect and export specimens for study, and to Ned Seligman, Roberta dos Santos and Quintino Quade of STePUP of Sao Tomehttp://www.stepup.st/, our “home away from home”. We gratefully acknowledge the support of the G. Lindsay Field Research Fund, Hagey Research Venture Fund of the California Academy of Sciences for largely funding our initial two expeditions (GG I, II). The Société de Conservation et Développement (SCD) and Africa’s Eden provided logistics, ground transportation and lodging (GG III-V), and special thanks for the generosity of private individuals who made the GG III-V expeditions possible: George G. Breed, Gerry F. Ohrstrom, Timothy M. Muller, Mrs. W. H. V. Brooke, Mr. and Mrs. Michael Murakami, Hon. Richard C. Livermore, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. Robert M. Taylor, Velma and Michael Schnoll, and Sheila Farr Nielsen; GG VI supporters include Bom Bom Island and the Omali Lodge for logistics and lodging, The Herbst Foundation, The “Blackhawk Gang,” the Docent Council of the California Academy of Sciences in honor of Kathleen Lilienthal, Bernard S. Schulte, Corinne W. Abel, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. John Sears, John S. Livermore and Elton Welke. GG VII was funded by a very generous grant from The William K. Bowes Jr. Foundation, and substantial donations from Mrs. W.H.V.“D.A.” Brooke, Thomas B. Livermore, Rod C. M. Hall, Timothy M. Muller, Prof. and Mrs. Evan C. Evans, Mr. and Mrs. John L. Sullivan Jr., Clarence G. Donahue, Mr. and Mrs. John Sears, and a heartening number of “Coolies”, “Blackhawk Gang” returnees and members of the Academy Docent Council. Once again we are deeply grateful for the continued support of the Omali Lodge (São Tomé) and Bom Bom Island (Príncipe) for both logistics and lodging and especially for sponsoring part our education efforts for GG VII and GG VIII. Substantial support has already come in for our next expeditions from donors in memory of the late Michael Alan Schnoll, beloved husband of our island biodiversity education Project Manager, Velma.
Our expeditions can be supported by tax-deductable donations to “California Academy of Sciences Gulf of Guinea Fund”

After two hectic weeks of education activities on São Tomé, Rayna Bell (Cornell University) arrived and the four of us joined the botanists, Tom Daniel, Jim Shevock, Miko Nadel, Tamas Szuts (our spider guy) and Andrew Stanbridge (our photographer) on Príncipe. I have asked Andrew, a veteran of three Gulf of Guinea expeditions, to illustrate some of what transpired while the group was divided.

All images by Andrew Stanbridge PARTNERS: We are most grateful to Arlindo de Ceita Carvalho, Director General, Victor Bomfim, and Salvador Sousa Pontes of the Ministry of Environment, Republic of São Tomé and Príncipe for their continuing authorization to collect and export specimens for study, and to Ned Seligman, Roberta dos Santos and Quintino Quade of STePUP of Sao Tomehttp://www.stepup.st/, our “home away from home”. We gratefully acknowledge the support of the G. Lindsay Field Research Fund, Hagey Research Venture Fund of the California Academy of Sciences for largely funding our initial two expeditions (GG I, II). The Société de Conservation et Développement (SCD) and Africa’s Eden provided logistics, ground transportation and lodging (GG III-V), and special thanks for the generosity of private individuals who made the GG III-V expeditions possible: George G. Breed, Gerry F. Ohrstrom, Timothy M. Muller, Mrs. W. H. V. Brooke, Mr. and Mrs. Michael Murakami, Hon. Richard C. Livermore, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. Robert M. Taylor, Velma and Michael Schnoll, and Sheila Farr Nielsen; GG VI supporters include Bom Bom Island and the Omali Lodge for logistics and lodging, The Herbst Foundation, The “Blackhawk Gang,” the Docent Council of the California Academy of Sciences in honor of Kathleen Lilienthal, Bernard S. Schulte, Corinne W. Abel, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. John Sears, John S. Livermore and Elton Welke. GG VII has been funded by a very generous grant from The William K. Bowes Jr. Foundation, and substantial donations from Mrs. W.H.V.“D.A.” Brooke, Thomas B. Livermore, Rod C. M. Hall, Timothy M. Muller, Prof. and Mrs. Evan C. Evans, Mr. and Mrs. John L. Sullivan Jr., Clarence G. Donahue, Mr. and Mrs. John Sears, and a heartening number of “Coolies”, “Blackhawk Gang” returnees and members of the Academy Docent Council. Once again we are deeply grateful for the continued support of the Omali Lodge (São Tomé) and Bom Bom Island (Príncipe) for both logistics and lodging and especially for sponsoring part our education efforts for GG VII. Our expeditions can be supported by tax-deductable donations to “California Academy of Sciences Gulf of Guinea Fund”